Methods of dispensing beverages are well known in the art. In a draft dispensing system, a beverage, such as a beer or ale, may be dispensed from a remote beverage container through a length of tubing to a spigot that may be open or closed by a draft handle. Pressurized gas, such as nitrogen or carbon dioxide, from a pressurized gas source is delivered to the beverage container to pressurize the beverage container. When the spigot is opened, a pressure regulator at the beverage container allows the beverage in the container to flow into the tubing and out the spigot. Other systems for dispensing beverages may utilize the pressurized gas to both carbonate and dispense the beverage.
Some beverages, which may typically consist of mixtures of ingredients, may require agitation to maintain the proper consistency of the mixture and to prevent separation of the ingredients. Dispensing systems for such beverages may include pumping systems that continuously circulate the beverage to maintain consistency. The pumping system may be powered from a source separate from the pressurized gas of a draft system, as the continuous pumping can quickly deplete the pressurized gas supply if used to power the beverage circulation system.
A system for dispensing a beverage from a tap may comprise a dispensing pump in fluid communication with the source of the beverage and the tap, wherein opening the tap operates the dispensing pump to pump the beverage from the source to the tap; and a mixing pump in fluid communication with the source of the beverage operable to circulate the beverage from the source, through the mixing pump and back to the source, wherein operation of the dispensing pump operates the mixing pump. The pumps may be operable by pressurized gas from a pressurized gas source and exhaust gas from the dispensing pump may be fed to the mixing pump to operate the mixing pump. A regulator may control the pressure of the pressurized gas seen at the mixing pump and the dispensing pump. The pressurized gas source may be part of a draft system for dispensing additional beverages.
A shut off valve may be disposed between the dispensing pump and the tap so as to stop the operation of the dispensing pump and the mixing pump when the beverage in the source falls below a predetermined level. The shut off valve may include a bypass between the shut off valve and the source of the beverage. When the bypass is activated, beverage may flow from the shut off valve to the beverage source causing operation of the dispensing pump and the mixing pump.
The system may include a bleed line disposed between the dispensing pump and the tap to provide a controlled flow from an output port of the dispensing pump to the beverage source. The controlled flow can lower a pressure at the output port of the dispensing pump to allow periodic operation of the dispensing pump to compensate for the pressure drop. A needle valve may be used to provide the controlled flow and a filter can be disposed upstream of the needle valve to minimize clogging of the needle.